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Virologist on outdoor contact risks/new variant

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 Bob Kemp 13 Jan 2021

Some useful information in this Twitter thread from virologist Muge Cevik of St Andrews University:

https://twitter.com/mugecevik/status/1348771251758784517

Suggests there is still much lower risk from outdoor contact although there's now more likelihood of encountering an infectious person. Good summary of the factors affecting transmission generally.

 Postmanpat 13 Jan 2021
In reply to Bob Kemp:

  I'm intrigued by the impact of "superspreader events".  I wonder if there is any good data and analysis of the relative impact of those against random transmission in public spaces etc. Is it possible , for example, that one person going to a house party and giving it to 50 people is much more important than 10s of thousands of randoms going to Sainsburys  wearing masks and socially distancing  (or going soloing at Burbage)?

  I recognise that if each of the 50 people infected at the party infect one other person there is a problem. But the core problem would have been the party. I suppose that my question is whether if, in a theoretical world, it were possible to stop such superspreader events totally, the rate of transmission would be low enough for it not to be a serious problem?

Post edited at 11:53
 girlymonkey 13 Jan 2021
In reply to Bob Kemp:

I'd say it's no surprise really, dilution is the solution to pollution!

Nice to have it confirmed though

 DaveHK 13 Jan 2021
In reply to Postmanpat:

> I suppose that my question is whether if, in a theoretical world, it were possible to stop such superspreader events totally, the rate of transmission would be low enough for it not to be a serious problem?

Superspreader events all seem to involve prolonged indoor contact with large groups of people so the current restrictions should stop them. Provided everyone follows the restrictions...

 wercat 13 Jan 2021
In reply to Bob Kemp:

> Suggests there is still much lower risk from outdoor contact although there's now more likelihood of encountering an infectious person. Good summary of the factors affecting transmission generally.

By divers means I try to avoid being within less than 10 metres of anyone while I'm out and I don't stick to paths.  Setting out before first light combined with that essentially eliminates the increased risk of meeting someone infected out of doors.  Also, starting out with the stars, satellites and moon still in the dark sky is good for the soul

yesterday a largish group was approaching my poisition as I descended a well known ridge.  By that time it was in sun so I descended snowy rocky ground out of sight to a very nice sonnenterrasse and had a hot drink

Post edited at 12:49
 wercat 13 Jan 2021
In reply to DaveHK:

there's a superspreader living 5 minutes walk from our gate - the village is not the safest place!  Her spreading also infected a major Eden Valley timber company

 TomD89 13 Jan 2021
In reply to Bob Kemp:

The key is the distinction between encountering an infectious person and having meaningful contact with an infectious person to the point of making transmission statistically likely.

She echoes my thoughts when she says:

"Of course, we still need to show respect to others and their personal space outdoors, even though it’s low risk. But a recurring theme on social media and in the news is shaming people for spending time outside, when really this is one of the safer places."

There are many other more pressing areas requiring attention when it comes to reducing infection rates, limiting outdoor activity should be the very last on the list. I don't want myself or anyone else confined to the same, grey 5 mile area for months on end, on balance it won't do any good for mental health or continuing lockdown compliance. 

 Ramblin dave 13 Jan 2021
In reply to TomD89:

Yes, agree. We saw this during the first lockdown - people spent weeks shouting at each other in increasingly hysterical terms about inconsiderate joggers and what constituted an unjustifiably long bike ride, and then as we started to get a bit more of a picture of what was going on and how the virus worked, we saw that big outbreaks were clustering around care homes, call centres, farm accommodation, Amazon warehouses and meat packing plants, with any remotely responsible form of outdoor exercise making, as far as I can tell, no meaningful difference. I kind of hoped that this time around we might have learnt something from that experience...

 elsewhere 13 Jan 2021
In reply to Postmanpat:

>   I'm intrigued by the impact of "superspreader events".  I wonder if there is any good data and analysis of the relative impact of those against random transmission in public spaces etc.

Effective track & trace generates that information.

>   I recognise that if each of the 50 people infected at the party infect one other person there is a problem. But the core problem would have been the party. I suppose that my question is whether if, in a theoretical world, it were possible to stop such superspreader events totally, the rate of transmission would be low enough for it not to be a serious problem?

I don't know the balance of superspreader events vs mundane events however I suspect the latter are more significant (infected person infects zero to a small number other people over a few days). If spread was superspreader events loads of them would be identified (e.g. fifty people I only saw at my work/party/school/choir/gym/church last week on Wednesday went down with Covid). 

Superspreader events (eg choir practice, church services) have been identified and superspreader locations (eg meat processing plants, care homes) have been identified. The vast proportion of those infected have been to no such identifiable event or location. 

So a theoretical answer to you theoretical questions is "no".

If the correct answer is "yes" then superspreading events are surprisingly invisible even to those infected. 

Post edited at 13:53
 Bonzkars 13 Jan 2021
In reply to wercat:

Burn her at the stake 

Can anyone explain what make the Kent variant more effective/ dangerous? Is it just that if 100 people were exposed to viral load X of the original variant for a set time, say 20 would be infected but with the new one maybe 40 are infected because it's better at getting in through mucous membranes? It's not as if it is even smaller and 'flies ' further or stays viable for longer on surfaces.

 DaveHK 13 Jan 2021
In reply to Ramblin dave:

> Yes, agree. We saw this during the first lockdown - people spent weeks shouting at each other in increasingly hysterical terms about inconsiderate joggers and what constituted an unjustifiably long bike ride, and then as we started to get a bit more of a picture of what was going on and how the virus worked, we saw that big outbreaks were clustering around care homes, call centres, farm accommodation, Amazon warehouses and meat packing plants, with any remotely responsible form of outdoor exercise making, as far as I can tell, no meaningful difference. I kind of hoped that this time around we might have learnt something from that experience...

I've been banging on about the pointlessness of this for a while now but it seems that many have just swung right back into action with the hysterical criticism of activities that have little to no impact.

In reply to elsewhere:

> Effective track & trace generates that information.

In that case we are FUBAR'd

 wercat 13 Jan 2021
In reply to Bonzkars:

I'm sure that she's getting enough from the rest of her household who caught it!

 wercat 13 Jan 2021
In reply to DaveHK:

I wouldn't say little or no impact - they make the perpetrator fitter and happier.  Stronger cardiovascular system  in older folk is definitely going to be of benefit if getting a serious illness.

 Chris H 13 Jan 2021
In reply to Bob Kemp:

Lots of people near me leaping into the road (high risk of being run over) rather than pass someone on narrow pavement (I would think virtually zero covid risk).

An interesting question is how likely is picking up new variant from being in the same supermarket space - but not neccesarily near to - as someone who is infectious.  This being the one unavoidable risk to myself.

 freeflyer 13 Jan 2021
In reply to Bob Kemp:

Thanks, she's a good communicator as well as clearly very knowledgeable. Great interview here:

https://www.sciencefocus.com/science/coronavirus-misunderstandings-muge-cevik/

"At the moment, the majority of public messages don’t really make sense."

And some good discussion of aerosols and airflow.

 elsewhere 13 Jan 2021
In reply to Wide_Mouth_Frog:

> In that case we are FUBAR'd

Even so, I think people would notice if they and a few of their friends/colleagues/classmates/congregation or fellow partygoers all got Covid at the same time.

 elsewhere 13 Jan 2021
In reply to earlsdonwhu:

>  Is it just that if 100 people were exposed to viral load X of the original variant for a set time, say 20 would be infected but with the new one maybe 40 are infected?

That's pretty much it. I'm not sure if it is known why it spreads more.

Post edited at 17:40
In reply to elsewhere:

Thanks.

 Yanis Nayu 13 Jan 2021
In reply to earlsdonwhu:

I’ve read that swabs taken from people with the new variant have higher viral loads than would be the case with the old/other variants. That means they’d exhale higher viral loads with the associated higher risk of transmission. 

In reply to elsewhere:

> Effective track & trace generates that information.

Ha ha ha ha ha ha ha ha ha.

Oh f*ck...

 ScraggyGoat 14 Jan 2021
In reply to Ramblin dave:

Another example of us not learning from history and ignoring overseas evidence, the Chinese had not only suspected but scientifically investigated and got to the pre-print stage by early April 2020 that it was unlikely to be transmitted outside:

https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1.article-info

While this was only one piece of research and required corroboration, we the must consider it served all UK administrations for the public to be blaming each other for transmission......rather than questioning what the government was going to do about truly at risk areas with high population density, deprivation, poor health, multi-occupancy dwellings, multi-generational households and places of work where it would spread fastest.

This was most epitomised by the SNP's stay away from the Highlands campaign because they are 'fragile communities' when in fact they were/are the most robust against Covid spread, yet they never ever once mention Scotlands inner cities as being the communities at greatest risk, or thought much about Schools and Uni's bar the political imperatives upon them at the respective crunch points....nothing to see here...look over there

Why was this ? Well no government likes to be seen to fail and they knew they couldn't meet WHO guidelines of test, test, test (and still can't; Scotlands testing rate compared to WHO advice is woeful).   They knew if people travelled around for outside recreation they would face a political backlash even if outside was safe.

Consequently it was politically expedient and easier to engender a stay away, stay at home strategy.

The thorny issues of testing, and of isolating the infectious away from their families and the community (as we used to do as witnessed by the relic TB and Flu hospitals on hills outside all our major cities and towns), or by covid hotels etc (e.g. Taiwan is doing) conveniently could be put to one side, at exactly the time it should have had full focus and developed as the main contingency, and the public warmed up to the ideas. They also completely ignored the idea of encouraging the population to get cardiovascularly fit to create more resilience. Fail to plan, plan to fail.

Lessons of history and the advantages of modern science, were squandered by our politicians.  They all based their plans on what they hoped would be the best outcome (e.g. if we lock down for long enough we can functionally eradicate it (what with high asymptomatic rates and a continuing low prevalence..aye right, even before considering re-seeding from elsewhere),  it will hopefully die by summer, or if we can get it low we can have Christmas) with no contingency, other than the lockdown approach.  Lock-down has its place once transmission is out of control, but with it now being endemic, with no effective test and trace, and community isolation available once lock-down is released we are/were stuck in a cycle till the vaccination rates become high enough to block....the question is how high is high enough? 

While I'm not advocating a free for all outside yet as infection rates are high, and the equivalent research for the outside transmissibility of the new variant is yet to completed, once the rates come down and the research jigsaw starts to fit into place (and if it indicates outside is safe, on balance it probably will) we need to allow people to get out.  The summer practically taught us what the Chinese researched, thousands of people can get out around Scotland so long as they stay outside, have minimal interaction and the base rate is relatively low).

Post edited at 11:14

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